Convection currents occur in the MANTLE. The mantle is the second layer of the earth after the crust. The mantle is approximately 2900 km thick. Convection currents are triggered or fueled by the heat from the Earth's core.
The part of the mantle closest to the core gets heated. It then becomes less dense than the layers above so it rises. When this rising plume interacts with the crust it cools and becomes more dense than the layers below and so it sinks and this circular motion continues to form convection currents.
Mostly its the tectonic plates that shift under us that causes earthquakes, how they shift changes the damage the earthquake can cause so tectonic plates unless u want the mythological one which is some earth god scratching his back
Soil liquefaction describes a phenomenon whereby a saturated or partially saturated substantially loses strength and stiffness in response to an applied stress, usually earthquake shaking or other sudden change in stress condition, causing it to behave like a liquid.
I think the answer is yes they can approve the decision to cancel Saturday mail but I’m not positive